On Sun, Oct 29, 2017 at 08:39:08PM -0600, Jim Fehlig wrote: > Hi All, > > It may be a foolish en devour, but I'm trying to make a qemu hook script > that provides the semantics of an old, custom xen block script. The script > parses <disk> info, does some setup based on that, and then rewrites part of > the config based on results of the setup. As an example, here is an XML > snippet of a <disk> device on input to the hook script > > <disk type='block' device='disk'> > <driver name='qemu' type='raw'/> > <source dev='some-dev-config'/> > <target dev='vdb' bus='virtio'/> > </disk> > > and XML returned by the script > > <disk type='block' device='disk'> > <driver name='qemu' type='raw'/> > <source dev='/dev/foo'/> > <target dev='vdb' bus='virtio'/> > </disk> > > The hook script performs the setup and substitution in the "prepare" phase, > but I noticed the results are never used when subsequently starting the > domain. Indeed qemuProcessStartHook passes a NULL buffer to virHookCall, so > the output XML of the hook is never collected. Does anyone have objections > to using the XML returned from the "prepare" and "release" hook script > phases, similar to how it is used in the "restore" and "migrate" phases? That was an explicit decision - we don't want hook scripts arbitrarily modifying the XML during startup. They're there to let you trigger external actions, but they're not there to let you modify the config. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
